import java.io.*;
import java.util.*;
import java.util.function.*;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        long[] singles = new long[26];
        long[] doubles = new long[26];
        long ans = 0;
        for (char c : sc.next().toCharArray()) {
            int idx = c - 'A';
            for (int i = 0; i < 26; i++) {
                if (i != idx) {
                    ans += doubles[i];
                }
            }
            doubles[idx] += singles[idx];
            singles[idx]++;
        }
        System.out.println(ans);
    }
}
class Scanner {
    BufferedReader br;
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() {
        try {
            br = new BufferedReader(new InputStreamReader(System.in));
        } catch (Exception e) {
            
        }
    }
    
    public int nextInt() {
        return Integer.parseInt(next());
    }
    
    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public double nextDouble() {
        return Double.parseDouble(next());
    }
    
    public String next() {
        try {
            while (!st.hasMoreTokens()) {
                st = new StringTokenizer(br.readLine());
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            return st.nextToken();
        }
    }
    
}